1. Field of the Invention
Embodiments of the present invention relate to a method and apparatus for perforating, stimulating, and producing hydrocarbon wells.
2. Description of the Related Art
A wellbore typically penetrates multiple hydrocarbon bearing zones, each requiring independent perforation and fracturing prior to production. Multiple bridge plugs are typically employed to isolate the individual hydrocarbon bearing zones, thereby permitting the independent perforation and fracturing of each zone with minimal impact to other zones within the well bore and with minimal disruption to production. This is accomplished by perforating and fracturing a lower zone followed by placing a bridge plug in the casing immediately above the fraced zone, thereby isolating the fraced lower zone from the upper zones and permitting an upper zone to be perforated and fraced. This process is repeated until all of the desired zones have been perforated and fraced. After perforating and fracturing each hydrocarbon bearing zone, the bridge plugs between the zones are removed, typically by drilling, and the hydrocarbons from each of the zones are permitted to flow into the wellbore and flow to the surface. This is a time consuming and costly process that requires many downhole trips to place and remove plugs and other downhole tools between each of the hydrocarbon bearing zones.
The repeated run-in and run-out of a casing string to install and remove specific tools designed to accomplish the individual tasks associated with perforating, fracturing, and installing bridge plugs at each hydrocarbon bearing interval can consume considerable time and incur considerable expense. Plugs with check valves have been used to minimize those costly downhole trips so that production can take place after fracing eliminating the need to drill out the conventional bridge plugs mentioned above. See, e.g. U.S. Pat. Nos. 4,427,071; 4,433,702; 4,531,587; 5,310,005; 6,196,261; 6,289,926; and 6,394,187. The result is a well with a very high production rate and thus a very rapid payout.
There is a need, therefore, for a multi-purpose combination tool and method for combining the same that can minimize the repeated raising and lowering of a drill string into the well.